DE1467045A1 - Process for the production of synthetic, crystalline, zeolitic aluminosilicates - Google Patents

Description

File number: P 14 67 045.2
Applicant: Esso Research ...

New documents for disclosure

ESSO RESEARCH AND ENGINEERING COMPANY, Elizabeth, New Jersey, V.St.A.

Process for the production of synthetic, crystalline, zeolitic aluminosilicates

For this application the priority will be from December 10, 1963 of the USA patent application 8er.No. 329 366 claimed.

The present invention relates to a process for the preparation of synthetic crystalline aluminosilicate zeolites, have the improved resistance at high temperature, wherein, the zeolite from an aqueous reaction mixture, one Solution or a sol of alkali oxides, silica and alumina are crystallized.

A process for the production of crystalline zeolitic molecular sieves is known, in which the crystals from be crystallized from an aqueous mixture of sodium-potassium-aluminosilicate at a temperature of 25 to 150 ° C, an aqueous silica sol is to be used as an essential component of the silicon-containing material.

(Art 7 11 Abe. 2 No. 1 Sertz 3 of the Anderunjwie «· * ♦ ·» · Wß?)

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It is a different method of making artificial ones Zeolites known, in which the extraction of aluminum salts by the decomposition of clay minerals, such as kaolin, bauxite or the like, with acids and / or acidic alkali salts remaining insoluble after the filtration Residue is used. Jüaboi is supposed to be the formation of the Zeolites are effected by boiling under pressure.

In a further process, which has not been previously published is, the crystallization is carried out above 4-0 ° C in the course of at least 20 minutes, giving the reactants diadoche ions with the coordinate numbers J, 4- or if necessary. 6 containing solutions are added, whereby an improvement of the adsorption properties is achieved.

In the process according to the invention, on the other hand, the reaction mixture contains an essentially water-insoluble inorganic metal oxide belonging to the rare oxides Earth metals or the metals of the second and fourth group of the periodic table, including mixtures of these Oxides can be used and the inorganic metal oxide is in the reaction mixture anyway at the moment is present, in which the crystallization of the zeolite is initiated, in an amount between 1 and 20% by weight, preferably 2 to 12 or 3 to 6% by weight, calculated on the weight of the zeolite, whereby a crystalline aluminosilicate zeolite is obtained which additionally contains a contains substantially water-insoluble inorganic metal oxide within its crystal lattice.

The zeolite is said to be a synthetic faujasite, a synthetic one Mordenite or a zeolite A. The crystallization takes place preferably at an elevated temperature in the range from about 82 to 120 ° 0, the reaction mixture being allowed to age for a sufficiently long time at this temperature, to obtain a crystalline zeolite.

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According to the invention, zeolite has a b'aujasite structure and is characterized in the anhydrous state by the following molar formula:

0.9 i 0.2 Na ₂ O: Al ₅ O ₅ : χ SiO ₂ ,

where χ has a value between 2 and 7 and the molar ratios of the reactants are within the following Moving boundaries:

SiO ₂ : Al.
C. 3 - 27 Na ₂ O : Al,
C. 1 - 11 H 0. : Öi ( 3 - 30 > ° 3 > ° 3

The zeolite can be treated with a cation exchanger to reduce the alkali oxide content to less than 10% by weight, preferably 1-5% by weight, to be reduced.

Preferably the zeolite is combined with a platinum group metal.

According to the invention is produced by this method Zeolite with a pore size of about 6 to 15 Å as Catalyst used.

The high temperature resistance of the zeolite is significantly improved by the incorporation of the metal oxide, which increases its value for the drying of gases, the conversion of hydrocarbons, etc. wixxi. When these modified zeolites are used as catalysts or catalyst supports in processes for the conversion of hydrocarbons (e.g., catalytic cracking, hydrogenating cracking, isomerization , etc.) , they exhibit significantly improved catalytic activity and selectivity for the desired product.

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According to a preferred embodiment of the invention, for example the reaction mixture is finely divided magnesium oxide prior to _t the crystallization of zeolites added. The resulting crystallized zeolite then contains a small amount of water-insoluble magnesium oxide, which is retained in its crystal structure and can only be removed with great difficulty by washing out with water or by ion exchange with solutions of metal ions. The process thus differs from the usual ion exchange of zeolites with a solution containing magnesium ions. In this case, the magnesium ions can be replaced by a more easily exchangeable cation by subsequent ion exchange.

A synthetic faujasite can be made from the reactants can be made in the following typical molar ratios:

Table I.

: Al ₂ O ₃ Generally until 27 Preferred 12th Particularly In particular until 8th : Al ₂ O ₃ 3 until 11 3-to 4th preferred 6th until 3 SiO ₂ : SiO ₂ 1 until 30th 1 to 20th 6. to 10 2 until 10 Na ₂ O 3 3 to 2 to 4- 7th H ₂ O 6 to 12

The above ranges are only typical values, but the invention is not limited to these ranges. In addition to the obfeen reactants practically water-insoluble inorganic metal oxide is added either in a finely divided, substantially pure, solid form or as a chemical compound which decomposes at a temperature below the crystallization temperature, for example below 99 ⁰ G, easy to virtually pure, solid form. The metal oxide can be added to the reaction mixture as a powder, finely divided gel or chemical compound which easily decomposes to the desired metal oxide, so that individual particles form from the metal oxide before the zeolite crystallizes. The metal oxide should be in a sufficiently finely divided state so that it is in

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the crystal structure of the zeolite that forms during crystallization is retained. Preferably the metal oxide is slurried in one of the main reactants, e.g. the alkali aluminate or the silica sol. It will be enough Metal oxide added to make a zeolite with a composition within the ranges given above forms. Upon crystallization, the metal oxide particles become held in the crystal framework of the zeolite.

The crystallization is usually stopped by quenching with excess water when the highest degree of crystallinity (determined by intermittent analysis) is reached. The product is then separated off from the reaction mixture by known processes, for example by filtration, centrifugation, etc., washed thoroughly and dried at higher temperatures, for example 10 4 to 158 ° C. After separation from the mother liquor and thorough washing, the crystals can be ^{activated by heating to 150 to 232 °} C., for example, in order to drive off water of hydration and to produce a practically anhydrous product which is suitable as an adsorbent and catalyst.

A synthetic "Zeolite A" which is an inorganic metal oxide contains, can-can be -followed by-the same procedure Use of the following molar ratios between the participants produce:

: Al ₀ O,
: Al ₂ O ₃
: SiO ₂ Table II Area 1 1.3
3.9
600 Area 2 until
until
until 2.5
7.5
600 until
until
until 1.3
1.0
35 SiO ₂
Ka ₂ O
H ₂ O 0.5
0.5
55

The amount of the metal oxide to be added is the same as described above for the preparation of the synthetic faujasite.

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A synthetic mordenite containing an inorganic metal oxide is made by crystallizing a mixture in which the participants in the following Molar ratios exist:

Tabel III until 12th SiO ₂ : Al ₂ U ₃ 8th until 3 Na ₂ O : Al ₂ O ₃ 1 until 75 H ₂ O : SiO ₂ 3

Here, too, the amount of the inorganic metal oxide is again the same as that described above for the production of the synthetic I? Aujasite. The crystallization can be carried out under pressure in a closed vessel at about 260 to 302 ^° C. in the course of about 8 to 72 hours at a pH of the reaction mixture of more than about 8, for example from 8 to 10.5.

The invention is not limited to the manufacture of those described above Types of crystalline zeolitic aluminosilicates limited. The determination of the stabilizing effect of the metal oxide added as a constituent on the crystal framework of the zeolite and its beneficial effect on the activity and selectivity of that produced from the zeolite The catalyst in the conversion of hydrocarbons is based on a wide variety of synthetic zeolites and theirs Manufacture applicable.

In addition to being useful as adsorbents, some of the crystalline zeolites, especially those, have them with uniform pore openings of about 6 to 15 Å and Silica to alumina ratios greater than about 3 » e.g. from 4 to 6, valuable properties as catalysts for the conversion of hydrocarbons.

The metal ion can be a cation of one of the metals of Groups I to VIII of the Periodic Table or the rare earth metals

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but is preferably a cation of a metal from Group II, III, IV, V, VI-B, VII-B or VIII of the Periodic Table of a rare earth metal. Particularly suitable metals for catalysts for catalytic cleavage are the alkaline earth metals, especially magnesium and calcium. The ion exchange can by slurrying the zeolite in an aqueous solution of the respective cation at temperatures of about 15 *> is 66 ⁰ C, leaching of soluble ions from the product of ion exchange and dry erfoxgeii. Suitable solutions are, for example, solutions of magnesium sulfate, calcium chloride, barium chloride, iron sulfate, ammonium hydroxide, ammonium chloride, etc. Typical known cleavage conditions are temperatures of about 400 to 565 ° C, pressures from atmospheric pressure to about 7 atü, etc.

This post-ion exchange treatment through which a Metal ion is introduced into the zeolite, however, must necessarily from the addition of the inorganic metal oxide to the Reaction mixture before the crystallization of the zeolite according to of the invention can be distinguished. In the case of subsequent ion exchange, the end result is the replacement of the Alkali metal, which forms part of the actual crystal structure of the zeolite, by another Metal ion instead, which can easily be exchanged further. The inorganic metal oxide, on the other hand, is hardly affected by the Ion exchange treatment affects.

With regard to the above-described modification of the zeolites for the purpose of producing dissociation catalysts, the process according to the invention offers a further advantage which has not yet been discussed. It has been found that the "magnesium form" of these zeolites is particularly suitable for cracking catalysts, and that improved catalysts are obtained when at least 75 % of the initial sodium is exchanged for magnesium. So the goal is to increase the magnesium content as much as possible and the

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Sodium content mc _u jerks down. The exchange for magnesium ions is rather slow, especially when the sodium content decreases. In addition, the reduction in the sodium content per exchange process is relatively small, which is why a large number of exchange processes are required in order to reduce the Na-O content below the equilibrium point, which is around 4 % sodium, as soon as this sodium content is reached the sodium and magnesium content is essentially constant unless the ion exchange temperature is increased significantly. As a result, the highest magnesium oxide content that can be achieved using the customary ion exchange processes is only about 6 to 9% by weight, based on the zeolite. According to the invention, however, a magnesium-containing zeolite is produced directly by adding magnesium oxide to the reaction mixture prior to the crystallization of the zeolite. During the subsequent ion exchange with magnesium ions, the usual amount of magnesium ions is transferred to the zeolite, so that, together with the previously introduced amount of solid magnesium oxide, the total magnesium content is considerably higher than could be achieved by known processes. According to this two-stage process, which consists of the previous addition of magnesium oxide in solid form and the subsequent introduction of magnesium ions by ion exchange, a total magnesium oxide content of up to about 18% by weight can be achieved.

The ion-exchanged zeolites that degrade you Have sodium content, can be used for certain purposes, such as the hydrogenative cleavage, further by soaking modified with suitable metals, e.g. hydrogenating metals. E.g. one can use the inorganic metal oxide containing, ion-exchanged crystalline, zeolitic aluminosilicate metals of the platinum group, such as Palladium, platinum and hhodium, or other metals such as molybdenum, Chromium, vanadium, cobalt, nickel, copper, silver and manganese. Preferably the zeolites are done first Ion exchange with ammonium ions partially freed from metal ions and. then with the corresponding metal salt or the

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corresponding ammonium complex compound of the chloride of the platinum or palladium treated. The amount of platinum metal in the finished catalyst is generally between about 0.01 and 5 »0% by weight, preferably from 0.1 to 3.0% by weight, based on the dry zeolite. Typical conditions for the hydrogenative cleavage are temperatures of about 288 to 538 ⁰ O, pressures of about 14 to 210 atmospheres, a feed rate of about 0.25 "to 10 parts by volume of starting material per part by volume of catalyst per hour and a hydrogen feed rate of about 13 "5-450 Nm ^5/100. 1

The zeolitic catalyst can be used in the forms described above for catalytic conversion processes or it can be in an amorphous substance, such as silica gel or a mixed gel made of silicon dioxide and at least another metal oxide, the metal from groups H-A, IH-A and IV-B of the periodic System is selected, such as aluminum oxide, titanium dioxide, magnesium oxide, etc. The use of such composite catalysts have proven to be valuable when working in the fluidized bed or with moving beds, because these catalysts can easily be processed into particles of the desired size. This compound Masses can be shaped by placing the zeolite crystals in a suitable hydrogel, e.g. silica-alumina hydrogel, incorporated, the mixture, if necessary with the addition of water, keeps it in vigorous motion to achieve a to produce liquid dispersion, and finally the mixture is subjected to spray drying. This subsequent treatment, in which the crystalline zeolite is incorporated into a predominant amount of amorphous gel is strictly from to distinguish the process of the present invention, which involves the addition of a small amount of an inorganic Metal oxide relates to the reaction mixture before the crystallization of the zeolite, so that one is a metal oxide containing zeolite, the improved high-temperature

ΘΟ9Θ13? 1ΌΟ1

λΌ

and water vapor resistance and improved catalytic Has properties when he is in marriage catalyst for the hydrogenative cleavage is converted.

example 1

A crystalline, zeolitic sodium inosilicate of the type of synthetic faujasite with pore sizes » about 13 Å is made as follows: A solution of

96 g of commercially available sodium aluminate (which contains 38% by weight Na ₂ O, 38% by weight Al ₂ O ₃ and 24% by weight HgU) and 3 ^ v1 '<- S

97% sodium hydroxide (75% by weight Na ₀ O) in 1229 g of water is added with stirring at room temperature to 2325ι6 g of a commercially available aqueous colloidal silica brine which contains 30% by weight SiO ₂ , and in which 12 g chemically pure magnesium oxide has been slurried. The reaction mixture is stirred until it is homogeneous and then heated to 100 ° C. within 6 hours and aged in a closed vessel for 5 1/2 layers at this temperature. At this point in time, a zeolite with a sufficient degree of crystallinity has formed. This is filtered off, washed with water until reaching a pH of 10 and dried at 100 ⁰ C.

The zeolite is then stirred for 5 hours at room temperature with 3500 ml of 19% ammonium chloride solution in order to reduce its Na ₂ O content . After washing out excess chloride ions with water and calcining at temperatures below about 510 ⁰ C, the finished product contains 71.5 wt .-% UiO 19,4- ₃₁ wt .-% Al ₂ O _5, 3.84 wt.% Na ₂ ~ O and 5.85 wt% MgO. The molar ratio of silica to alumina in the product is 6.25: 1 and X-ray diffraction analysis shows the typical structure of the faujasite.

In order to investigate the high temperature resistance and water vapor resistance of the product, some samples are provided at

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AA

Temperatures between 538 and 815 O and other samples aged in the presence of water vapor at 565 to 64-9 ^{0 C.} The results of these stability tests are given in the table below as degrees of crystallinity of the various samples compared with a standard sample of synthetic fgujasite, the degree of crystallinity of which is arbitrarily set as 100.

Table IV Stability of crystalline zeolite containing Hannesium Oxide

Heat treatment Kristallini
degree of efficiency,
determined by
X-ray diffraction
% of the norm
sample Specific
surface
m ² / g I.
Pore volume
ml / g 16 hours at 538 ^° C 115 509 0.69 16 hours at 760 ^° C 107 74-2 0.54- 16 etd. at 815 ° C 96 616 0.62 with water vapor
16 hours at 565 ° E
treated 124 500 0.67 with steam
16 hours at 64-9 ° C
treated 107 303 0.69

It follows that those containing the magnesium oxide Samples are extremely stable under these harsh conditions and retain their crystal structure to a high degree. One similar treatment of samples which do not contain magnesia results in substantial decomposition among them extremely harsh conditions. This demonstrates the improved durability that results from the an inorganic metal oxide Crystalline zeolites containing reaction mixtures obtained during the crystallization, eiie peculiarity of the resulting zeolitic crystal framework is.

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Example 2

Sin crystalline zeolite with the structure of "Zeolite A" with pore sizes of about $ 15, according to Example 1, however ;, from a reaction mixture with the following molar ratios manufactured:

Al ₂ O _{5 m} 1.3

The colloidal silica sol used for the reaction contains 6 wt .- $> Kagnesiumoxyd, _f Dezogen on the final product .. The Zeoiith "has improved Hoehtemperaturbeständigkeit

Example g

A crystalline zeolitic sodium aluminosilicate, which contains amorphous zinc oxide, is prepared according to * Example 1 from a 'solution of 90.4 g of sodium aluminate solution _y 560 g of sodium hydroxide and 2246 g of water, to which 6720 g of SO% silica sol are added ^ in which previously 4 -5 g of zinc oxide powder have been slurried on. Daa Sid—. · - 'product shows the typical structure of the Fau ^ & siiiSwUnd ^^ ent ^ · - "■ .. ·. · Contains 64.7 % SiO ₂ , 20 ^ 4 % Al ₂ O ₅ ^ 12 * _r 4 % N & ₂ 0 _h 2 _r 36% ZnO. The pick-up ratio of silica and alumina is 5.4: 1.

.-_. ■ ";'-. · ■ - ■'. ' - ■ '■■ - ■' - '■: .--'"· ^ 3 ^ i *. ¹ \ ⁱ ~ '~ iiii .-.'"I<i. Tt Example 4

H8W3h dem. "Werfaiu? Ea of example 5..will, Zeolite l> annoyance, estelliF, the

learweadet, 120 g

4214 g, Vtetsser,

sol imd 22,, 1 g ^ alpi ^ uROxyd ·. The EadpiOduct. eathäit 14 ^, 2 wt

ORIGINAL INSPECTED

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i ι

Beimel 5 U67045

In the procedure of Example 3, the zinc oxide is replaced by finely powdered silica-alumina. One receives a crystalline, zeolitic sodium aluminosilicate, which contains silicon dioxide-aluminum oxide in its crystal structure.

Example 6

Example 3 is used, but lithium oxide is used instead of zinc oxide

Example 7

Example 3 is followed, but beryllium oxide is used instead of zinc oxide

Example 8

Example 3 is used, however, cerium oxide is used instead of zinc oxide.

Example 9

Example 3t is used, but lanthanum oxide is used instead of zinc oxide

Example 10

To explain the use of the zeolites produced according to the invention for catalytic cleavage, the synthetic, crystalline, zeolite sodium aluminosilicate produced according to Example 1 and containing magnesium oxide is subjected to three ion exchanges with magnesium sulfate solution after crystallization, filtration and washing.Each treatment lasts 1 hour and is with a solution of 143 g of HgSO ₄ · 7 H ₂ O in 2236 ml of water. In this way, the sodium content of the zeolite is reduced by replacing it with magnesium ions. After this

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Washing, drying and calcining the product contains 4.3% by weight Na ₂ O, 12% by weight MgO (of which 6% by weight is accounted for by the previously added magnesium oxide), 66.9% by weight SiO ₂ and 15.0 wt% Al ₂ O ,. According to X-ray diffraction analysis, it is a typical ffaujasite.

This product is mixed with a silica hydrogel in a ratio of 1 rope of zeolite to 9 parts of steamed hydrogel and the mixture is processed into shaped bodies for a dissociation catalyst. These catalyst bodies are used in an operating with Buheschüttung catalytic test cracking unit at a temperature of 515 ⁰ C, atmospheric pressure, a feed rate of 0.69 parts by weight per part by weight of catalyst per hour and an operating time of 30 minutes to determine the cleavage activity. The starting material has a specific gravity of 0.8586, a boiling range from 260 to 360 ° C, an aniline point of 77.2 ° 0, a sulfur content of 0.2 wt .- #, a bromine number of 3.0 and a pour point of + 4.5 ° C

The performance of the catalyst is determined by comparison with the performance includes a conventional, normal silica-alumina gel catalyst, of 25 wt .- # alumina, and bits that of a conventional normal silica-magnesia gel catalyst rated, of the 30 QEV .-% magnesium oxide contains · the following table shows the Proäctverteilung obtained with the individual catalysts at the same conversion level of 62.3% (the degree of conversion is the percentage of Ausgangsguts, to be below about 221 ⁰ O is converted boiling products).

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45 *: ■> ■

Table Ύ.

Rating yon. Split catalysts Comparison of the product distribution at 62.5% ip; em

Crystalline
Zeolite with
, 12 wt.% MgQ ,,
embedded in
: Silica gel i More normal
\ Silicic acid
ion earth
i catalytic converter “Normal
; Silica
;Magnesia-
catalyst Carbon,
Wt .- #; ; 4.6 ! ^7vr ■ i 5 » ⁷ G ₄ "gas ; 15.1 , 25.0 ί 20.0 petrol
(G ₁ - Ms 221 Ο,]
.7 · ■■ ■ , ^ r7, I 51, .0 I ⁵ 7, o, .Λ ..

As the above Oiabelle shows _y Fuart the containing of magnesium oxide crystalline zeolite and "silica existing Katalysato-r zxt generating a nledrigerea carbon, a lower G ^ -Gäs generating ümcb a correspondingly higher '~ BenzinfeildtajQg al & the two known Spaltlcatalysat <? REII. i convenient Wirloang of Einschlusses- d, so a verbes ^ ert-e3a Sgalt ^ ermsSgea it · aiaorganischen Metalloxydes' in the EristafellgeiKlst of ^ eoliths leads ZVL the AAI this Zeolitheähör-

In order to explain; The use of the zeolites produced according to the invention in the hydrogenating, cleavage is a syathetic, crystalline ^ aeoHitMschesi N ^ triumaluminosilicate, which has a slightly pulverulent; Mjagaesiumox ^ ä in his Kxi & tailgsriätst, contains _λ HÄßhi example 1 with diem

The difference is that the crystallization time is reduced to 4 3/4 days and the ion exchange with ammonium chloride is carried out as follows: The sodium form of the zeolite is treated in three stages with 19% ammonium chloride solution. The first treatment takes place for 5 hours at room temperature, the second and third each for 2 hours at 66 to 71 ^° C. After washing with water and drying, the Na ₂ O content is only 2.2% by weight.

This zeolite is converted into a catalyst for the hydrogenative cleavage by slurrying 179 g of the same in 1 l of water and adding 57 ml of ammoniacal palladium chloride _{solution (ie Pd (NEL) 4} Cl ₂ ) containing 0.012875 g of palladium per ml to the suspension with stirring contains, be added. After further 2 hours of mixing, the catalyst is filtered off, washed with water and dried at 100 ⁰ C. The product contains 2.2% by weight Na ₂ O, 6.0% by weight MgO, 68.4 _{% by weight SiO 2} , 20.8% by weight Al ₂ O, and 0.5% by weight. - # Pd and shows the structure of a typical faujasite according to X-ray diffraction analysis.

This catalyst for the hydrogenative cleavage is classified and heat-treated for the purpose of evaluation in small test systems in the quiescent bed. The catalyst is used to produce pills of 4.76 mm 2.38 mm, which are then comminuted for testing for particle sizes of 0.50 to 1.41 mm. The heat treatment is performed via 16 hours of passing a dry air stream over the catalyst in a muffle furnace at 149 ⁰ C, after which the temperature slowly at a rate of 55 ° C / hr. increased to 538 ^° C. and held at 538 ^° C. for at least 3 1/2 hours. As a result of this latter treatment, most of the ammonia is discharged from the catalyst, for example to less than 0.003% by weight.

The catalyst produced in this way is poured into a bed in a plant compared to a normal catalyst which has essentially the same composition but none Contains magnesium oxide.

8 0 9 8 1 37 1 0 0 f

/ I f-

Light catalytically split cycle oil with a boiling range from 220 to 345 ^° C. and a nitrogen content of 40 ppm is used as the starting material for the hydrogenative cleavage. At a pressure of 70 atmospheres, a temperature between 549 and 371 ⁰ O, a feed rate between 2.7 and 4.0 parts by ^{volume of starting material o e} part by volume of catalyst per hour and a hydrogen supply rate of about 142 Bnr / 100 1 of starting material, the The following values are obtained: The relative activities of the two catalysts are determined by comparing the percentage degree of conversion to products boiling below 221 ° C (measured by D ₊ L Engler distillation), corrected for the conditions of temperature, pressure, gas velocity and feed rate of the starting material according to known correlation methods.

Under these conditions, the two catalysts had practically the same selectivity; their relative activities however, were the following:

Table VI

Normal catalyst without MgO 1.00 catalyst with MgO 1.98

It follows from this that the catalyst containing the magnesium oxide is about twice as active as that of no magnesium oxide containing normal catalyst.

It was also found that on the catalyst containing the magnesium oxide after 220 hours of operation only about 1/3 as much carbon had accumulated as on the normal catalyst:

Table VII Carbon deposition

V * Operating hours

_{Normal catalyst ΛΓ}
without MgO ^Ίϋ

Catalyst * ₉ * ₂ 20

with MgO 3, / P

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The heat resistance of the two catalysts at 827 ° C. was also investigated. The catalyst containing the magnesium oxide retains its crystallinity to a higher degree than the known catalyst, which is evident from the X-ray diffraction spectra. In the following table, the percentage degree of crystallinity relates to a similar normal catalyst (whose degree of crystallinity is assumed to be 100 wix'd), which is not exposed to extremely harsh heat conditions.

Table VIII Heat resistance at 627 ° Q

Degree of crystallinity, ° / o of the standard sample

Normal catalyst without MgO 13 catalyst with MgO 44

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Claims (8)

I. Process for the preparation of synthetic crystalline Aluminosilicate zeolites which have improved resistance at high temperature, the zeolite being composed of a aqueous reaction mixture, a solution or a sol is crystallized from alkali oxides, silicic acid and alumina, characterized in that the reaction mixture is essentially water-insoluble Contains inorganic metal oxide, belonging to the oxides of the rare earth metals or the metals of the second and fourth Group of the periodic table, mixtures of these oxides can also be used and the inorganic Metal oxide is present in the reaction mixture in any case at the moment in which the crystallization of the zeolite is introduced, in an amount between 1 and 20 wt .-%, calculated on the weight of the Zeolite, whereby a crystalline aluminosilicate zeolite is obtained, which is additionally an essentially water-insoluble contains inorganic metal oxide within its crystal lattice. 2. The method according to claim 1, characterized in that the zeolite is a synthetic faujasite, a synthetic Mordenite or a zeolite A. 3. The method according to claims 1 or 2, characterized gekennzeüinet that the crystallization takes place at an elevated temperature in the range of about 82 to 120 ⁰ C, the reaction mixture is allowed to age at this temperature long enough to obtain a crystalline zeolite. 4-. Process according to Claims 1 to 3, characterized in that that the zeolite has a faujasite structure and in anhydrous state is characterized by the following molar formula: 0.9 ί 0.2 Na ₂ O: Al ₃ O ₃ : χ SiO ₂ , where χ has a value between about 2 and 7 and the molar ratios of the reactants are within «. <· 'RifortepSn (Art. 7 ff T half of the following limits move: SiO ₀ : Al ₀ O _x
dd t> 3 ■ Na ₂ O: Al ₂ O ₃ 1 - H ₂ O: SiO ₂ 3 - - 27 - 11 - 30. 5. Process according to claims 1 to 4, characterized in that that the zeolite is treated with a cation exchanger to reduce the alkali oxide content to less than 10 To reduce wt .-%. 6. The method according to any one of claims 1 to 5 »characterized in that that the zeolite is combined with a platinum group metal. 7 · Catalyst, consisting of a synthetic anhydrous Metal-aluminosilicate zeolite, characterized in that it contains about 1-20% by weight of an inorganic metal oxide contains within its crystal lattice, which is able to improve the temperature resistance of the zeolite, this metal oxide belonging to the group of rare earth metals or groups II and IV of the periodic System belongs and can also consist of mixtures thereof and wherein the zeolite has uniform pore openings has about 6 to 15 Å units and is treated with a cation exchanger to increase its alkali oxide content less than 10% by weight. 8. Catalyst according to claim 71, characterized in that the zeolite is a synthetic faujasite that is associated with a Platinum group metal is combined. 809813/1001